TV Soundbar Explained

What is a TV soundbar?

A TV soundbar is an elongated speaker system with a very shallow depth. It combines multiple speakers into a single enclosure and is designed as a simple plug-and-play solution. Once connected and turned on, it replaces the TV’s weak sound with a significantly richer sound experience, without the need to set up a full home theater system. It is precisely this simplicity that has made soundbars a popular solution for improving TV sound.

Multiple speakers in a single enclosure

Various drivers work together inside the slim enclosure. Small tweeters reproduce the delicate high frequencies, while midrange drivers cover the range where voices and most instruments fall. This combination creates a wider soundstage than the tiny speakers in a TV can produce. The length of a soundbar is often roughly equal to the width of the TV (or slightly less), so it doesn’t look out of place.

Flat-screen TVs often have poor sound quality

Modern TVs are designed to be extremely thin, and that’s exactly the problem. To produce a full, deep sound, a speaker needs a certain amount of cabinet volume to serve as a resonance chamber. Thin TVs simply lack this volume. As a result, the built-in sound often comes across as extremely flat, and quiet passages in particular get lost among the music and background noise. A soundbar provides the missing volume and components from an external source, compensating for this design-related weakness.

Soundbar, Sound Deck, and Soundbase

The classic soundbar is the flat bar that is placed in front of or below the TV or mounted on the wall. In addition, there is the sound deck, also known as a soundbase, a subcategory with a significantly greater depth. You can place your TV directly on top of a sound deck. Because it offers more enclosure volume, these models often come with built-in bass drivers that face forward or downward. However, unlike a soundbar, a sound deck cannot be mounted on the wall.

Soundbar or Traditional Surround Sound System

For many people, the key question before making a purchase is whether a single soundbar is enough or whether they should opt for a traditional multi-channel system. Both options result in better sound, but they differ in key aspects such as cost, space requirements, and sound quality.

Facilities and Space

A classic 5.1 system consists of several individual speakers that must be placed throughout the room and connected with cables. It usually also includes a separate AV receiver as the control center. This produces the most immersive sound, but requires space, cabling, and some technical know-how during setup. The soundbar flips this principle on its head by housing the most important speakers in a single unit. This eliminates the need to run long cables to front, rear, and center speakers, and keeps the setup looking neat and tidy.

Basis for Decision-Making

If you’re looking for maximum, precisely localizable surround sound for a true home theater experience and have the space for it, you’re often better off with a multi-component system. For most living rooms, however, a soundbar is the ideal compromise, offering low setup effort, a clean design, a clearly audible improvement in sound quality, and good value for the money. The line between the two is blurred, as many soundbars can be expanded into a small surround sound system by adding a subwoofer and wireless rear speakers.

Sewer Systems

The figures in the data sheet provide examples of how many channels make up the sound. Once you understand the system, you can quickly classify the models.

What the Numbers Mean

The first number refers to the main speakers at ear level, the second to a separate subwoofer, and a third number, if present, to upward-firing tweeters. A 2.0 soundbar therefore delivers pure stereo sound, a 2.1 adds a subwoofer, and starting with 5.1, channels for the room are included. There’s no upper limit to the scale. Systems like 7.1 or 7.1.4 add additional rear and height channels, and at the high end, there are elaborate configurations such as 9.1.4 or 11.1.4. However, such large systems usually only achieve their full potential with additional rear speakers and upward-firing drivers—not with a single soundbar alone. So more channels do not automatically mean better sound, as drivers, the room, placement, and signal processing all play a role.

The Center Channel for Dialogue

A dedicated center channel—that is, the first channel starting from three—is particularly important for speech intelligibility. It reproduces voices and dialogue specifically from the center, separate from the music and effects on the other channels. This makes spoken passages easier to understand, even during loud scenes. Systems without a dedicated center channel, on the other hand, mix the voices into the main channels, which is barely noticeable during quiet moments but quickly reaches its limits when the audio gets hectic. However, how clearly dialogue comes through ultimately depends not only on the center channel but also on signal processing and many other factors.

How a Soundbar Creates Surround Sound

A TV soundbar is usually placed in front of the TV, yet it’s designed to fill the entire room with sound. This is made possible by a combination of physical principles and signal processing.

Virtual Surround and Reflections

Since there are usually no speakers behind the sofa or the person watching TV, soundbars use virtual surround sound. Specially oriented drivers direct sound toward the side walls and ceiling, from where it is reflected back toward the listening position, creating the impression that it is coming from throughout the room. In addition, digital signal processing selectively adjusts frequencies and delay times so that the listener perceives a wider and deeper soundstage than the soundbar’s narrow design would otherwise allow. These psychoacoustic tricks work well, but they depend heavily on the shape of the room and the reflective surfaces.

Dolby Atmos and Sound from Above

Modern 3D audio formats like Dolby Atmos and DTS:X take it a step further. Instead of rigidly assigning sound to individual channels, they use an object-based approach. In this context, “object-based” means that individual sound objects are assigned coordinates in three-dimensional space. The device calculates in real time which drivers reproduce a given object, so that, for example, a helicopter in a movie actually seems to be coming from diagonally above. Upward-facing drivers project sound toward the ceiling, and the resulting reflection is perceived as the upper sound plane. This creates a sound dome above the sofa without the need to mount speakers on the ceiling.

The Subwoofer and the Bass

The reproduction of low frequencies is crucial for delivering a sense of impact during action scenes or when listening to music. This is exactly where you can see what a TV soundbar can do on its own—and when a separate subwoofer makes sense.

Limitations of a Soundbar

Low frequencies require a lot of moving air and, therefore, a large enclosure volume. A very slim soundbar can hardly provide that, which is why the bass often sounds thin without additional support. Some all-in-one models designed for smaller rooms still manage to deliver a decent foundation thanks to clever enclosure design and built-in woofers, but they rarely produce a powerful bass experience.

Internal and external subwoofer

Many soundbar systems therefore come with a separate subwoofer that is designed specifically for low frequencies. Today, it’s usually connected wirelessly to the soundbar and can be placed anywhere in the room. If you also isolate the subwoofer from the floor—for example, by placing it on a mat—you can prevent unwanted vibrations from being transmitted to furniture and adjacent rooms.

Connections and Joints

How a soundbar is connected to the TV determines sound quality and ease of use in everyday life. These differ primarily in bandwidth—that is, in how much audio data they transmit.

HDMI ARC and eARC

The standard used today is a connection via HDMI ARC—short for Audio Return Channel—or the newer variant, HDMI eARC. Using a single HDMI cable, the TV sends the audio back to the soundbar. The advantage of this is that the volume of the entire system can still be controlled using the regular TV remote (CEC protocol). The enhanced eARC variant offers significantly higher bandwidth and transmits audio virtually uncompressed, which is important for high-resolution formats such as Dolby Atmos. However, for eARC to work, both the TV and the soundbar must support this variant.

Optical Connection and Wireless Connection

If there is no suitable HDMI port, the optical digital input via a TOSLINK cable remains a solid alternative. However, this option has limited bandwidth. Additional connection options are available via Bluetooth or Wi-Fi. These allow you to wirelessly stream content from other devices, such as cell phones or tablets, as well as from streaming services. Due to frequent latency issues, both methods are better suited for music than for full TV audio. For TV audio, the HDMI connection is the better choice.

Position, Room Size, and Sound Modes

Even a very good soundbar will only sound as good as its placement in the room and its settings allow. There are three points that deserve special attention.

1. The Right Position in the Room

Ideally, the soundbar should be positioned centrally below the screen and as unobstructed as possible, so that nothing blocks the sound. Shelves, books, or a deep wall unit in front of the soundbar dampen the sound and interfere with the reflections on which virtual surround sound is based. If the device is recessed too deeply into a piece of furniture, some of the effect is lost. Some models offer automatic calibration via an app, which uses test tones to adjust the sound to the room.

2. Choose a TV and room that go well together

The size of the system should be appropriate for the TV and the room. In a small room, a bulky system can quickly sound boomy. In this case, a more compact TV soundbar is the better choice. In large, open spaces, on the other hand, the impact of a small, entry-level model is lost because the sound gets lost in the vast space.

3. Sound modes such as Night Mode and Voice Mode

Various sound modes allow you to adjust the sound to suit the content and time of day. A Voice or Clear mode boosts the midrange frequencies where voices are located. This makes dialogue slightly easier to understand, even at low volumes. A night mode attenuates loud peaks and boosts quiet passages. Additional profiles for movies, music, or sports adjust the sound settings to suit the genre. However, these modes work with the audio as the soundbar receives it from the TV. They do not replace targeted speech processing when intelligibility is the primary concern.